act of faith

American  

noun

1. an act that demonstrates or tests the strength of a person's convictions, as an important personal sacrifice.

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act of faith British  

noun

1. Christianity an act that demonstrates or tests a person's religious beliefs

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act of faith Idioms  

1. Behavior that shows or tests a person's religious or other convictions, as in Rock climbing with a new, inexperienced partner was a real act of faith. The term is a translation of the Portuguese auto da fé, which referred to the sentencing and execution of heretics (often by burning at the stake) during the Inquisition, when punishing heresy was thought to constitute an assertion of faith. In modern times it is used for more benign circumstances. [Early 1700s]

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Example Sentences

"I have been witnessing miracles of healing through the years because of this act of faith."

From Barron's • Apr. 3, 2026

For now, the preparations are an act of faith.

From The Wall Street Journal • Jan. 11, 2026

“But Jesus stresses the importance of belief. To proclaim that Jesus is our lord and savior is an act of faith that everyone has to take on their own.”

From Los Angeles Times • Nov. 25, 2025

For them, a pilgrimage to Mazu's home temple in Meizhou in southern China is an essential act of faith.

From BBC • Dec. 29, 2023

For most of the student demonstrators, however, nonviolence wasn’t simply another strategy such as picketing or sitting in; it was an act of faith.

From "The Best of Enemies" by Osha Gray Davidson